Women are more resilient and have a longer life expectancy than men, despite the fact they tend to be more frail and have poorer health in old age.
The surprising findings came from a narrative review on frailty published in the Medical Journal of Australia on Monday.
The researchers defined frailty as a state of increased vulnerability that's associated with poor health outcomes.
Just over 10 per cent of community-dwelling adults aged 65 years and up are frail, wrote researchers Emily Gordon, a consultant geriatrician, and Ruth Hubbard from the Centre for Health Services Research at the University of Queensland.
“A frail older person takes longer to recover after any sort of insult (such as infection, infarction or adverse drug reactions) and during the period of recovery is more vulnerable to further stressors," Dr Gordon and Professor Hubbard wrote.
"Increasing frailty is associated with syndromic disease presentations; falls, delirium, functional decline and new urinary incontinence may reflect acute illness in a frail older person and should never be dismissed as ‘normal for age’.”
The ‘sex-frailty paradox’
The researchers described the differences in frailty between men and women as the “sex-frailty paradox”.
“In community dwelling populations aged over 65 years, women are more likely to be frail and to have a greater burden of frailty than men of the same age,’’ they wrote.
"Yet women appear to be more resilient – at any given age or level of frailty, their mortality rates are lower.
“In Australia, the life expectancy of females continues to be about four years longer than that of males.
"Yet throughout their lives, women are burdened by chronic disease and disability to a greater extent than men and, unsurprisingly, women have poorer self-rated health.”
Read more: Two big killers put brakes on Australia’s life expectancy boom
In Australia, a boy born from 2015 to 2017 can expect to live to the age of 80.5 years, while a girl would be expected to live to 84.6 years, Australian Bureau of Statistics figures show.
Men aged 65 in 2015 to 2017 could expect to live another 19.7 years (an expected age at death of 84.7 years) and women aged 65 in 2015 to 2017 could expect to live another 22.3 years (an expected age at death of 87.3 years).
In their review, the researchers examined the evidence about frailty interventions. Exercise and nutrition-based interventions were found to have the highest levels of evidence.
“Many of these interventions target phenotypic features of frailty, including weakness, slowness and wasting,” they wrote.
“Yet frailty is more than just physical signs and symptoms. Cognitive training strategies and comprehensive geriatric assessment with interdisciplinary interventions address important non-physical health domains.
“More recently, researchers have reported benefits from multifactorial interventions incorporating exercise, a nutritional intervention, and cognitive training with social support or medication review.
“It is also important to note that very few studies have examined interventions to prevent the development of frailty in non-frail older adults.
"Further, the evidence base for interventions to prevent or reduce frailty in institutionalised or hospitalised older adults is limited.”
Some evidence implies that some interventions work better for one sex than the other, Dr Gordon and Professor Hubbar wrote.
“Sex differences in the effectiveness of interventions have not been specifically addressed by the research literature to date,” they wrote.
“Exercise programs appear to be effective in both sexes. However, sarcopenia, low physical activity and functional impairment are more prevalent in older women than men, and it is possible that women may benefit from a different type or intensity of exercise intervention than men.
“With respect to nutrition, men may benefit from interventions to a greater extent than women. Several studies have indicated that men tend to have a poorer understanding of nutrition and make unhealthy dietary decisions.
“Sex differences in frailty highlight that older men and women may respond to interventions in different ways and may benefit from more sex-specific strategies.”
There is a growing need for further research into frailty, and particularly the sex-frailty paradox, Dr Gordon and Professor Hubbar wrote.
“To provide optimal, patient-centred care, sex differences should inform our practice,” they wrote.
“While the evidence base for sex-specific frailty interventions is lacking at the present time, the knowledge gleaned and hypotheses generated from observational data should inspire programs of research, instigate public health initiatives, and prompt reflection by health professionals."